Electric field-enhanced electrochemical CRISPR biosensor for DNA detection

DNA detection plays an important role in the rapid screening of cancers and early diagnosis of infectious dis-eases. Here, we developed a simple, versatile, electric field-enhanced (EFE), electrochemical CRISPR biosensor to detect DNA targets in a homogeneous solution phase. To improve the detection sensitivity, we applied a pulsed electric field to enrich nucleic acids on the electrode surface. The EFE electrochemical CRISPR biosensor takes advantage of the diffusivity difference between electrochemical oligonucleotide probes and CRISPR-cleaved probes toward a negatively charged working electrode, enabling simple and sensitive electrochemical detec-tion of DNA without the need for complicated immobilization processing of electrochemical probes. Our developed CRISPR biosensor directly detects unamplified human papillomavirus-16 (HPV-16) DNA with a sensitivity of 1 pM. Further, the EFE electrochemical CRISPR biosensor coupled with recombinase polymerase amplification (RPA) successfully detects HPV-16 DNA in clinical samples. Thus, the EFE electrochemical CRISPR biosensor provides a simple, robust, and sensitive detection method for nucleic acid-based molecular diagnostics.

Automated summary

The developed EFE electrochemical CRISPR biosensor is a simple, versatile tool for detecting DNA targets in a homogeneous solution phase, achieving sensitive detection without the need for complicated immobilization processing. By leveraging electric field enhancement and diffusivity differences, the sensor provides a robust and sensitive method for nucleic acid-based molecular diagnostics.